Wick-type liquid fuel hand torch having wick-fed retort



Feb- 17, 1953 H. SHERMAN ET AL WICK-TYPE LIQUID FUEL. HAND TORCH HAVINGWICK-FED RETORT Filed Feb. 8, 1949 .fer

o bonen Patented Feb. 17, 1953 WICK-TYPE LIQUID FUEL HAND TORCH HAVINGWICK-FED RETORT Harry Sherman, Waban, Myer Allen Silverman,

Newton Center, and Hyman Liberman, Belmont, Mass.

Application February 8, 1949, Serial No. 75,242

6 Claims.

This invention relates to the art of ame or heat propagators principallyof the type including liquid and gaseous fuel burners adapted to providea concentrated heating effect at a predetermined area or point, as inconnection with mechanical operations. More particularly it pertains toheating devices of the portable fiame producing type, and in itspreferred adaptations, the invention is directed to liquid fuel blastlamps, especially exemplified by hand torches.

The age-old and widely diversified industrial use of blast lampsreflects the generally `acceptable function of these 'devices availableto the prior art. Possibly in some measure the comparatively limitedactivity in the progressive development of some types of theseappliances may be attributable to this situation. Neverthelesscommercially available devices in this category are not entirely freefrom legitimate elements of criticism. Thus by way of illustration,notwithstanding the generally satisfactory functioning of hand torchesin their innumerable fields of adaptation, various difficulties andobjectionable details have been experienced in their charaoteristics.

Illustrative of the difficulties and shortcomings attributable to handtorches, for example, has

' been their unnecessary complication. This is indicated by involving intheir structure movable parts introducing the necessity for periodicadjustment and resulting in points of mechanical weakness as well asundue wear. Moreover such difficulties as troublesome fuel leakage havebeen manifested by prior art devices due to their inherent mechanicalcharacteristics both with respect to structure and the restrictedangular position in use for which they have been designed.

- In addition there has been a necessity for recurrent cleaning of thetorches heretofore available, in view of the charring and cloggingeffects of carbonaceous material developed by their operation. Ingeneral the prior art devices have not afforded the maximum efiiciencyattainable either with respect to the heating characteristics developedor in connection with the functioning time for a given size of handtorch. Nor have they afforded optimum simplicity, compactness andsturdiness of structure together with an efiiciency of operationpursuant to the features of the present invention.

The optimum embodiment of structure on which the present invention ispredicated involves a complementary positioning of the fiame or primertube in contiguous association with a power or pressure chamber. Whilethe broad aspects of such an association have been con- `templated bythe prior art, there has been a 2 complete lack of realizationconcerning the relative coordination of these members in a manneraffording maximum efficiency in heating effect as well as in functioningtime for a given size of device involving a given volume of fuel. Inaddition the device described herein is constructed in accordance withfeatures of maximum simplicity both from the standpoint of initialassembly as well as in connection with maintenance during operation, andinvolves a minimum number of parts which are expediently coordinated atthe time of manufacture and thereafter require essentially no adjustmentor maintenance Within reasonable limits. e

It is an object of'this inventionto obviate .difficulties anduncertainties of the type vherein-- above indicated. Y

Another object is to provide a liquid fuel burner of the flame producingtype adapted to afford a maximumefficiency of heating effect at apredetermined area or point of concentration for a given size of deviceand volume of fuel utilized.

An additional object is a portable blast lamp of enhanced heating andoperative efficiency, adapted to afford a maximum functioning time underoptimum conditions for a given size of device and volume of fuelutilized.

An important object is to attain a hand torch of comparative structuralsimplicity, compactness and sturdiness, and adapted to afford anenhanced heating and operative efficiency including a maximumfunctioning time under optimum conditions for a given size of device andvolume of fuel utilized. v

An additional significant object is to produce a hand torch manifestingcomparative structural simplicity, compactness and sturdiness, yadaptedto afford an enhancedheating and operative Vefciency including a maximumfunctioning time under optimum conditions for a given size of device andvolume of fuel utilized, said device being essentially free fromdetrimental carbonizing and clogging effects and requiring a minimum ofadjustment and maintenance.

Other objects, advantages and features of the invention will becomeapparent from the following description read in connection with theLaccompanying drawing, in which similar elements are designated by likenumerals.

Fig. 1 is a vertical section of a preferred embodiment of hand torchWithin the purview 0f the present invention.

Fig. 2 pertains to a vertical section of a cap structure applicable tothe upper portion of the hand torch as a top closure when the device isnot in use.

Fig. 3 is directed to a cross section taken along the line 3-3 of Fig.1.

Fig. 4 comprises another cross sectional View, applicable to line 4-4 ofFig. 1.

Fig. 5 relates to a vertical section of the coupling or bushing at theupper end of the torch housing as shown in Fig. 1.

Fig. 6 represents a cross sectional detail showing the closure assemblyat the bottom of the flame or primer tube.

A preferred embodiment of the invention described herein comprises theouter housing of the device determining the power or pressure chamber,with a primer or flame tube chamber, the open-ended upper or outletportion of which projects upwardly from the power chamber housing withthe remainder thereof positioned within the said power chamber and insubstantial measure coextensive therewith. The volume capacity of thepower chamber, apart from that utilized by the ame tube positionedtherein, is preferably in excess of that of the said flame tube, anddesirably the volume relationship for fuel retention by the two membersbay be in the proportion of approximately 2:1, and may be substantiallylarger. Both the power chamber and flame tube are provided withcontiguous, easily removable bottom caps, whereby the tube chamber andpower chamber are expediently suppliedwith fuel from the bottom portionof the device. rihe gooseneck, provided 'with an vorifice nozzle,projects from the upper portion of the power charnber in preadjustedrelationship relative to the outlet of the name tube. Both the wickingof the flame tube andthe wick'extending from the Vgooseneck into thepower chamber may be of cotton or glass ber, and the device as a whole,free from soldered joints as well as from movable oper ative parts, issusceptible to expedient threaded assembly of the various membersthereof under essentially leakproo-f conditions.

Referring more particularly to the features of `invention embodied inthe modification shown by the various figures of the drawing, the torchdevice may involve an outer housing I, compris-ing the power or pressurechamber. The bottom end portion 2 of said housing I is surface threadedfor coordination with the internally threaded. cap member 3, whichdetermines the closure for the said housing. Desirably a washer element4 is appropriately seated within said cap member 3 for attaining aleakproof attachment of the cap member with the aforesaid housing I. Thesaid element 4 may expediently be in the form of a disc having adiameter conforming with that of the inside surface I9 of the said capmember and desirably sufficient to result in its being fittedly wedgedtherein, thereby completely covering the said surface I9. If desired, aslight groove may be provided in the walls of cap 3 adjacent surface I9wherein the periphery of washer 4 may be fittedly wedged.

The upper end 5 of housing I is fitted with a coupling or bushing 6,which is in effect the integral top member of the housing- It will benoted that this coupling in effect comprises a lower portion I and anupper portion 8 of relatively reduced dimension, with a peripheralshoulder or flange 9 between the said portions. The said lower vportionI of the coupling is prov-ided with an internal thread I0 forcoordination with the externally threaded portion II of the housingwhereby the said coupling or bushing 6 is attached to the said housing.

The upper portion 8 of coupling 6 is threaded on its peripheral surfaceto permit the attachment thereto of top cap I2 which is supplied at thelower portion I3 thereof with internal threads I adapted for associationwith the said surface threads of coupling portion 8. Thus as will beseen from the dotted line rindication of Fig. 1, the cap I2 affords afitted removable top closure for the housing I, and thereby for theentire torch assembly, with the bottom portion I3 of the cap beingseated on the aforesaid annular ange 9 of coupling 6.

An opening I5 is provided through the top of coupling I3, -this being ofa diameter adapted to receive the primer or flame tube IG. Thus theinternal threads I1 on the Iinner surface of upper portion B of thebushing or coupling 6 are coordinated with the peripheral threadedsection I8 of flame tube I6, whereby the flame tube is in effectsupported by the said coupling 6 or housing I to which the coupling itattached. It will be seen that the flame tube I6 extends from a pointoutside housing I, through opening I5 of bushing 5 to which it isthreadedly attached, and thence to a point substantially near the bottomof the housing I, determined by the inner surface I9 of cap member 3, orat least by the washer element 4 seated therein.

The lower end portion 2li of tube I6 is desirably threaded on itsinternal surface in order to receive the externally threaded surface ofbushing 2I. The threads 22 on the vinternal surface of said bushing 2Iare ladapted to receive the externally threaded end or stem 23 of fillerplug 24. The said filler plug thus ln effect determines the bottomclosure of flame tube IS, and thereby vdefines the flame tube chamberhaving a closed bottom and an open upper or outlet portion 32.

In order to render the bottom closure of flame tube I6 leakproof,bushing 2I is .countersunk on its bottom surface adjacent the openingtherethrough to provide a seat 56 for washer element 25. The said washerelement 25 is of the conventional design having an opening through whichstem 23 of plug 24 may pass. Thus the screwed attachment of plug 24 tobushing 2| results in the compression of the said washer element atleast partly into said countersunk seat 56 as well as against flange 26determined by head 21 of the said plug 2li. As an expedient forfacilitating the attachment or removal of filler plug 24, the outersurface 28 of head 2l may be supplied -with a slot or groove 29 for thepurpose of effecting the use 0f a screwdriver or coin.

The said outer surface 28 of plug 24 is shown as desirably positionedrelatively close to the inner surface of cap member 3, said innersurface being shown as a resilient gasket I9, but preferably affordingan intervening space 30 determining a zone between the bottom of theflame tube and that of the power chamber within which some of the fuelcontained within the said housing I may be present. It will however beunderstood that notwithstanding the desirability of providing such anintervening zone, this is not entirely essential to the operativefunctioning of the device. Thus the outer surface 28 of ller plug 24 maybe in contact `with inner surface I9 of cap member 3 with the effectthat the volume content of the power chamber determined by annular space3l circumventing flame tube IB is accord-ingly diminished.

The upper portion 32 of flame tube I6 substantially projects abovehousing I, as shown in Fig. 1. The said end portion 32 of name tube I6is substantially filled with an appropriate wick ma- A terial which maydesirably extend from opening 55 of the tube to some expedient pointtherein which may desirably be below the comparable level of the lowerend of bushing 6 to which the flame tube is attached as previouslyindicated. Thus the mass of wick material 33 in effect may extend withinflame tube I6 from its opening 55 to a portion thereof which is withinhousing I, and it may be retained in position by the frictional contactof the mass against the inner wall surface of the flame tube I6 byvirtue of the quantity of wick material utilized, or in any otherexpedient manner, as by a wire spring element coordinated with the wickmass. Ex-

tending from the lower portion of this mass 33.-

of wicking, a wick 34 of relatively lesser diameter is provided,extending from the lower portion of wick mass 33 to substantially thebottom of flame tube I6 contiguous the inner end of filler plug 24. Inorder to appropriately support wick 34 in its extended position, theupper end thereof may be expediently positioned within wick material 33.If desired, the upper end of wick 34 may extend through wick material 33to any expedient point up to opening 55, it being understood that theupward extent of wick 34 is determinable by discretion from thestandpoint of the requisite retention thereof in its functioningposition within the flame tube. Thus wick 34-is adapted to be immersedin any fuel contained within flame tube I6, and the portion thereofwithin end 32 of the flame tube is desirably enveloped by the aforesaidmass 33 of wick material.- The wick material utilized may be of cottonor glass derivation as desired.

The actual power chamber comprises the aforesaid annular space 3|between the outer surface of flame tube I6 and the inner surface ofhousing I. The said power chamber 3| is preferably in excess of thevolume content of flame tube I6, as previously stated. Without intendingto restrict the relative volumes of power chamber 3| to flame tube I6within the scope of the invention, an optimum type of torch is affordedwhere the volume content of said power chamber 3I is in the proportionof approximately 2:1 with respect to the flame tube volume, or greater.Thus while the device is effectively operative where the relative volumerelationship of the flame tube and power chamber may approximate 1:1 inview of the other features applicable thereto, the optimum embodimentsof the invention contemplate for the relationship between the fuelvolume content of the' power chamber and that of the flame tube theproportion of approximately 2:1 and even substantially in excessthereof, such as 3:1 or 4:1 for example. The significance of thecoextensive relationship of llame tube and power chamber, with theformer positioned within the latter, and the latter affording arelatively larger volume content, will be referred to in theconsideration hereinbelow.

Referring again to coupling 6, a second and relatively smaller opening35 is provided adjacent to the aforesaid Opening I5. As previouslydescribed, flame tube I6 projects above coupling 6 through said openingI5 as well as being attached to and supported by the coupling along theperipheral surface of this opening. On the other hand, gooseneck 36 isaffixed to coupling 6 at the said opening 35 from which it projectsupwardly. Thus the lower portion 31 of the gooseneck is surface threadedfor coordination Y with the threads on the surface of the coupling .A6within said yopening 35. The uppercurved end 38 of gooseneck 36 islikewise peripherally threaded for reception of the internal threadsprovided on orifice nozzle 39. The orice is designated at 40. As will beseen from Fig. 1 showing the torc retained in upright position, theopening 55 at end 32 of flame tube I6 is inclined rather than occurringin a horizontal plane. The lower end of the opening is relativelycontiguous to gooseneck 36, and desirably adjacent the lower portion 31thereof, as at a point substantially midway between the curved portionof the gooseneck and the end thereof attached to coupling 6. The angleof inclination from the horizontal of said opening 55, that is, itsangular disposition relative to the transverse axis of the flame tube,may desirably be between approximately 20 and-30, although it will beunderstood that this may be subject to reasonable variation withoutdeparting from the fundamentals of the invention herein. This angulardisposition of opening 55 may be of material significance particularlywith respect to the coordination of the said opening with the variousparts of the gooseneck 36.

Thus when the gooseneck is afhxed and adjusted for use, nozzle orifice40 is positioned above and in reasonable proximity to said opening 55 offlame tube I6, and it is desirably spaced somewhat off center, that is,offset from the vertical or longitudinal axis 51 extending through thecenter of flame tube I6. Pursuant to the preferred adaptation of theinvention, orifice 40, while being opening 55,y does not approach theprojection of axis line 51 which passes through substantially the centerof flame tube opening 55. The extent of deviation from the axis may berelatively small, and by way of illustration approximately M34 to J/g"has been found quite satisfactory. This expedient results in asubstantially enhanced heating effectiveness in the flame emanating fromorifice 4U. K

Without intending to be restricted kto any theory or explanation, itwill be seen that the angular disposition of opening 55 provides anenlarged wick surface and corresponding flame generated by the saidflame tube I6. The correlation of the lower end of the opening inrelative contiguity with portion 31 of gooseneck 3S serves to preheatthe latter and thereby the vapors passing therethrough. At the sametime, the flame at 55, by virtue of its position relative to curved end38 of gooseneck 36 functions to substantially envelop the entire nozzle,particularly when the torch is in relatively upright position, therebylikewise preheating the vapors passing throug`h`38 as well as the nozzle39. In effect the coordination of the gooseneck with flame tube opening55 as described affords a preheating of the fuel, including thevolatilized portion thereof, in its passage through a substantial extentof the gooseneck. In addition the aforesaid angular characteristics ofopening 55 serve to provide an effective llame for vapors evolved atorice 40 at substantially any practicable position in which the torchmay be retainedv for utilization. Thus the flame at opening 55 isoperatively and efliciently coordinated with vapors issuing from orifice40 at substantially any torch angle, except possibly when the torch issupported in inverted position.

Accordingly the improved heating efficiency attributable to thecoordinated features of angularly disposed flame tube opening 55 andgooseneck 36 appears to be attributable in substantial measure to a morecomplete ignition ofthe pressure now of combustible vapors emittedthrough orince 4B'. A further advantage is the added range torchoperativeness provided, this comprising the eilici'ent functioning ofthe torch at substantially any angle from its upright position, short ofcomplete inversion. This latter feature may be understood from arealization that the tendency of the flame at opening 55 is to seek anupward direction, irrespective of the angle at which the torch is heldfor use, and the offset positioning of nozzle 40 retains the flow ofvapors therefrom in an area of combustible relationship with opening 55notwithstanding the said angular disposition of the torch assembly untilthe torch approaches substantially complete inversion` Inoontradistinction, any substantial angular retention of prior arttorches results in the orifice being out of combustible relationshipwith the flame intended to ignite the vapors issuing therefrom with theresult that the device is rendered essentially inoperative and uselessat any substantial departure from the vertical or upright position ofthe torch.

A Wick 4I is seated within gooseneck 36 and extends from the orificenozzle attached thereto to a point substantially contiguous innersurface IS of cap member 3. Thus Wick 4I is positioned within powerchamber 3| and is ccextensive with flame tube I6 as Well as wick 34positioned within the latter. Similarly to wick material 33 and wick.34,said Wick 4I may effectively be of cotton or glass fibre derivation.

As shown in Fig. l, cap I2 comprises a closure for the entire torchassembly, by virtue of its threaded attachment to the upper portion 3 ofcoupling 6, the latter being in turn integrally attached to housing I.Thus cap I2 envelops the portion I8 of flame tube I6 which projectsbeyond housing I, as well as the gcoseneck 35 and the orifice nozzle 39in unitary attachment relative thereto. When thus enclosed by the saidcap member I2, it will be apparent that the operative portions ormembers of the device are enclosed and substantially protected fromdisturbance or damage, with the assembly as a whole comprising a simple,compact, sturdy structure. In the interest of expediency, attachmentsare applied to cap member I2 for maintaining the same in convenientposition with respect to the torch, and also for affording an effectivemeans removably mounted on the cap member and adapted for obviating anyclogging of orice 46.

Thus cap member I2l is provided with opening 42 through the top thereof,said opening being appropriately threaded to receive the peripheralthreads on threaded stern portion. 45 of cleaning pin plug 46. Integralwith stem 45 and positioned within the same is member or tube element 4Iwhich serves as the support for cleaning wire or pin 48, the said pin orwire being in unitary attachment to member or tube 41. Said pin 48 isnecessarily of a dimension adapted for insertion within orifice 40 forthe purpose of removing obstructions therein resulting from anyextraneous material, illustrated by carbonaceous formation as a resultof the fuel combustion taking place during the operation of the torch.In view of the association of the various parts as described, the pinplug 46 is attached to cap member I2 when not in use, thereby beingconveniently supported in a manner which minimizes the possibilities ofits loss or of any inconvenience relative to the operation of thedevice. In order to utilize pin 48 it is merely necessary to unscrew pinplug 45 from cap member I2 and to insert the pin in orifice 40.

For purposes of an expedient leak prooi attachment, the washer 50,having an opening adapted for a relatively snug t over stern 45 of pinplug 46, isv resorted to and on aflixing the plug to the threadedopening 42. of cap member I2, the washer will be compressed between thehead of the plug and the outer surface of said cap member.

An expedient manner for attaching the pin plug 46 and cap member I2 tothe torch assembly comprises a bead or link chain 5I provided witheyelets 53 at the respective ends thereof. One eyelet is retained inposition on the top surface of piny plug 46 through the expedient ofheaded pin 44, the latter being permanently attached to the pin plug,but projecting above the same sufciently to afford a swivel or freeassociation therewith of the said eyelet 53. Similarly the other` eyeletof the chain is attached in the same ty-pe of loose or swivelassociation to portion I of bushing or coupling E through pin 49 whichis integral with the said coupling portion I. With this attachment ofchain 5I to coupling 6 at one end and pin plug 46 at the other, the pinplug will remain suspended from the torch duringr the use thereofwithout any hazard of loss. In this manner, the cleaning pin plug isalways maintained in a convenient position for use with a. minimumhazard of loss.

This situation will apply whether or not cap member I2 is attached tohousing I in its capacity as a closure of the assembly or during theinterval when the cap member is removed from the housing in order topermit the use of the device. If the plug 46 remains affixed to cmpmember I2 when the latter is unscrewed from housing I, it will beapparent that the cap member will be retained in suspended proximitywith respect to the body or housing of the torch. Conversely, ifdesired, the cap `member may be separated from plug 46 during theinterval of torch use, and in that event merely the pin plug per se willbe supported by chain 5 I.

t should be further noted that other expedients for attachment of pinplug and cap member may be relied upon. Illustratively the opening 42 ofthe cap member may be threaded to receive the peripheral threads of abushing, the lower portion oi the latter within the cap member being inthe form of a flange. This bushing may be internally threaded to receivethe threaded stem 45 of the cleaning plug. As in the showing of Fig. 2,stem 45 may be supplied With a tube member 41 to which -pin 48 isintegrally affixed. By resort to a chain provided with clips aty therespective ends thereof, one clip may be seated over the aforesaidflange at the lower por- -tion of the bushing and may desirably beseated in a groove provided on the said flange. Thus upon attachment ofthe bushing to the opening of cap member I2, the chain clip will beretained in situ between the flange and the inner surface of the capmember. Under such circumstances, the cap member is in a more or lesspermanent association with the chain. The clip at the other end of thechain may envelop the vertical portion 3l of gooseneck 36. By such anassociation, the chain plug and cap member are retained in substantiallypermanent association with the chain, with the pin plug being removablefrom the cap member for use of the cleaning pin.

In the operation of the torch, it is fir-st supplied with the -fuelcontemplated for use. The fuel utilized is within the discretion ofthose skilled in the art, and may desirably be an alcohol, such as ethylor denatured alcohol. In this connection, the housing is held in inverseposition, with the knurled surface cap member 3, comprising the bottomclosure, positioned at the top. The cap member is deta-ched byunscrewing the same from housing I, and fil-ler plu-g 24 is thensimilarly removed yfrom flame tube I6, by resort to some such expedientas a screwdriver or coin inserted in slot 29 for rotating the said plugfrom its closed position. The liquid fuel is then supplied to flame tubeI6 until the receptacle is substantially completely filled, whereupon'ller plug 24 i-s reattached. Liquid fuel is then added to power chamber3 I, and when this chamber is substantially but not entirely filled, toafford a space for pressure development, cap member 3 is again attachedto housing I, thereby completely closing the assembly, with th-e fuelcontent therein. During this interval of supplying the predeterminedfuel, cap member I2 may or may not be retained in its position as a topclosure for the assembly. With the device supplied with fuel, it i-sadapted for utilization, when the said cap member I2 has been removedfrom attachment to upper portion 8 of coupling 6 integral with housingI. In order to propagate the heating llame, it is merely necessary toignite the fuel absorbed by the wick material 33 at the opening 55 offlame tube I6.

Without intending to be restricted to any theory or explanationconcerning the operation of the devi-ce, it is submitted that as theresultant flame develops at the tube opening 55, the heat propagated isconducted by the walls of the flame tube chamber, including flame tube I6 and the bottom closure 24 thereof, in heat exchange relationship withthe fuel within power pressure chamber 3|. As a result of immersion ofthe flame tube chamber I6 in the fuel of power chamber 3|, with thelatter preferably being of a substantially enlarged volume content ascompared with the said flame tu-be chamber, the temperature within theflame tube containing wick 34 and a wick .material 33, is maintainedunder comparatively controlled conditions which in effect prevent anyexcessive temperature that might cause boiling over of fuel from thesaid flame tube chamber. Thus the fuel in power chamber 3| is adapted tofunction as a cooling bath for the flame tube chamber immersed therein,and is in turn subjected to heating by the aforesaid heat exchange tothe extent that vapor-ization or volatilization of liquid fuel withinpower chamber 3| is manifeste-d. At the same time, the coordinatedassociation of flame tube opening 55 with gooseneck 36 res-ults in theflame at opening 55 heating a substantial lportion of the gooseneck,including particularly the nozzle thereof which, as previouslyindicated'may be substantially enveloped by the flame, as well as thecurve p-ortion 38 and an adjacent part of upwardly extending portion 31of the gooseneck.

With the generation of vapor or gas from the liquid fuel in powerchamber 3|, a pressure is developed therein, and through the expedientof wick 4| at its upper portion Within gooseneck 36, the volatilizedfuel is directed to orifice 4|] of said gooseneck 36. The predeterminedrelative position of orifice 40 to the flame at opening 55 of the flametube results in projecting and igniting the gas or volatilized fuelemanating from orifice 4U, under the prevailing pressure conditionswithin power chamber 3|, as augmented bythe supplementary heating effectof the gooseneck as described above, through the 10^ said flameandopening 55 resulting in the ignition of the gas, and the flame blast isthereby propagated for utilization.

By immersing the flame tube chamber Within the power chamber ofrelatively greater volume, with the immersed portion of the flame tubebeing substantially coextensive with the power chamber, an enhancedeiciency of heat exchange and attendant torch operation is attainable.As previously indicated, due to the heat conductivity of the flame tubechamber, the fuel within the power chamber is subjected to requisiteheating throughout the body of fuel therein, and at the same time theflame tube is desirably subjected to an effective cooling.

In other words the cooling and the heating effects are attained by heatexchange at precisely the proper zones within the torch housing to avoidundue propagation of Vapor within the flame tube and the desiredpressure development within the power chamber. There is thereby affordeda maximum interval of operation before refueling becomes necessary,under the most efficient conditions, for a given quantity of' fuelwithin a torch of a given volume content. This improved efficiency ismanifested by a maximum concentration of heat in the pressure chamber3|, with an attendant acceleration of vapor development therein and acomparatively increased attendant pressure. In effect this situationserves to render the torch quicker starting, with an increased rate ofheating, and a higher flame temperature development than that heretoforeattainable with blow torches of comparable size. Indicative of theefficiency of hand torches pursuant to the present invention, a flameblast of approximately 4 inches to 6 inches, dependent upon the size ofthe torch, and of substantial maximum heating effect, may be attainedwithin approximatelyv ten. seconds from the time the wick at opening 55is ignited, and` the temperature attainable is approximately 1800 F.

Moreover the preferred embodiment of device as described requires merelyan adjustment of the parts involved during the course of assembly, sincethe details of construction lend themselves to a permanent or fixedassociation of the various members determining the construction. Thusthe stationary power chamber and gooseneck attached thereto, as well asthe stationary flame tube are relatively positioned atthe time thedevice is assembled, and in view of the elimination of moving parts, noperiodic adjustments are necessary for optimum operation. Furthermore byvirtue of the structural characteristics, the torch contemplated by theinvention generally lends itself to utilization in a diversification ofangular positions without any substantial hazard of leakage or effect onthe heating efficiency determined by the flame blast developed.v Thusthe torch within the purview of the invention.

is essentially foolproof in its function and efficiency of operation.

The novel characteristics of the device are additionally manifested bythe simplicity, compactness and sturdiness of the assembly, as well asthe substantial elimination of maintenance and repair requirements. Incontradistinction to conventional practice, the blow torch of thepresent invention is substantially exclusively dependent upon a threadedattachment of the various members to each other, and the usual brazingand soldering resorted to in connection with these devices is avoided.In this manner,

the assembly of the parts is facilitated, and the possibility of leakageat soldered, brazed or welded joints is essentially eliminated. At thesame time, the respective parts of the device are easily accessible forany replacement, and the device as a whole lends itself to expedientcleaning or substitution of parts, should this be deemed advisable. Aspreviously indicated, the elimination of moving parts in connection withthe operation of the device reduces structural wear and mechanicaldifficulties to a minimum, although in the event of any defectivemembers, these may be expediently replaced.

Contributing to the facilitated maintenance of the structurecontemplated is the substantial lack of carbonization tendencymanifested by the torch of the present invention in the use of cottonwicking. This advantageous effect appears to be attributable to theburning characteristics of the torch, including the enhanced pressure ofthe volatiles issuing from the orifice 40, and the substantiallycomplete combustion of these volatiles as Well as the fuel propagatingthe flame at opening 55 of the flame tube by virtue of the temperatureand conditions of combustion attained by the operation of the device.

This substantial reduction in carbonization avoids the necessity forfrequent replacement of wicks even under extreme conditions of torchuse. Moreover the adaptation of wicks of glass fibre derivation to thetorch of the present invention essentially obviates any charring orcarbonization, even under the most adverse conditions of operation, andincluding the situation where the fuel supply within the torch ispermitted to run dry, since glass wicking affords a maximum resistanceto the effect of temperature under the conditions prevailing in a blastlamp and in effect manifests no charring action. Thus either with cottonor glass wicks relied upon for the functioning of the device of thepresent invention, the necessity for frequent replacement of wicks isnot encountered.

It will be understood that the specific material of which the variousmembers and parts are fabricated has no critical bearing on the featuresof the invention and is determinable from expedience as well aspreference. Thus while the flame tube I6 should preferably be of a heatconducting material, desirably metal, the particular choice of metal issubject to variation within reasonable discretion. Metals affordingeffective heat conducting characteristics which are adapted for theflame tube are illustrated by copper, copper alloys, aluminum andso-called red brass or duralumin. An expedient metal utilized compriseshigh quality brass plated with a chromium finish.

Similarly the housing may be of any expedient material, although in thisconnection, the heat conducting properties may not be especiallysignificant, dependent upon the characteristics of the device. Thus thehousing may effectively be made from any expedient heat non-conductingmaterials as Well as from the usual metals used in fabricating torchhousings.

Likewise the washers utilized are subject to variation as to thematerial involved, although neoprene washers have been found quitesatisfactory in view of their wear resistant attributes and heatinsulating properties. Moreover as stated hereinabove, the resort toglass wicking may comprise a preferred type of material for thepertinent parts of the structure, in view of the characteristicsthereof, although as previously stated, the use of cotton wicking in thedevices of the present invention has been quite satisfactory. Withfurther reference to the wicking, the mass in end 32 of the flame tubemay result from one or more Wads of appropriate material, the totalamount being 4sufficient to retain its position in the indicated part ofthe tube. It will, however, be understood that any expedient manner ormeans may be resorted to for retaining in desired position either thewicking in 32 or any of the other Wicks utilized. In brief it will beunderstood that the latitude of the invention contemplates theutilization of other types of materials than those mentioned, dependentupon the particular characteristics of the torch contemplated as well asthe discretion of those skilled in the art.

It will accordingly be noted that the invention is predicated on a noveltype of blast lamp, particularly that in the category of a blow or handtorch, and embraces among its features structural simplicity,compactness, sturdiness and particularly an enhanced efficiency andfacility of construction as well as operation. The attributes andadvantages of the invention described are apparent from its novelfeatures as manifested by its details of construction. Moreover in viewof its utility, the invention lends itself to a wide field ofadaptation.

While we have described our invention in accordance with a preferredembodiment thereof, it is obvious that many changes may be made in thedetails of construction and in the combination of parts and materials,without departing from the spirit of the invention as defined ln thefollowing claims.

Having thus set forth the invention, we claim:

1. A blow torch comprising a closed housing having a removable bottomclosure and a top member, said housing determining a power chamber,means forming a flame tube chamber of a volume content less than that ofthe power chamber, said flame tube chamber having an open upper end anda removable bottom closure and mounted Within said housing, said flametube chamber being substantially coextensive in length with said powerchamber but short of the lower end of said power chamber and supportedonly by said top member, the open ended portion of said flame tube beingpositioned above said top member outside the housing, a comparativelyshort conduit communicating with said power chamber, said conduit beingprovided with an orifice outlet and attached to said top member of thehousing, said orifice outlet being positioned above and substantiallydirectly over the open end of said flame tube chamber, in proximity toand in heat exchange relation with any flame at said open end, wickmeans within said flame tube chamber adapted for conveying liquid fuelfrom said flame tube chamber to the open end thereof, and Wick meanswithin said conduit and power chamber for conveying fuel from the powerchamber to said orifice.

2. A blow torch as in claim 1, including a, fitted top closure for saidhousing removably attachable to said top member and adapted to envelopboth the open ended portion of the flame tube positioned outside thehousing and the comparatively short conduit communicating with the powerchamber.

3. A blow torch as in claim 1, wherein the oomparatively short conduitcommunicating with the power chamber comprises a gooseneck providedwith-said orifice outlet.

4. A blow torch as in claim 3, wherein the `said. orice outlet is offsetfrom the longitudinal axis extending through the center of the flametube and. the open end thereof.

5. A blow torch as in claim 3, wherein the open end of the flame tubedetermines an opening in an inclined plane relative to the transverseaxis of the llame tube, the said opening extending downwardly toward.said gooseneck and terminating' in relative proximity to the verticalportion of the Said gooseneck, said open end of the flame tube beingsubstantially filled with a wick mass.

6. A blow torch as in claim 5, wherein the said orifice outlet is oisetfrom the longitudinal axis extending through the center of the flametube andthe open end thereof.

HARRY SHERMAN. MYER ALLEN SILVERMAN. HYMAN LIBERMAN.

REFERENCES CITED The following references are of record in the le o1.this patent:

Number Number 1 4 UNITED STATES PATENTS Name Date Rosenbrook Oct. 28,1902 Snow Mar. 11, 1919 Schneider Nov. 4, 1919 Folgman Feb. 10, 1920Schmitt Sept. 4, 1923 Folgman Sept. 16, 1924 Stanezyk Aug. 25, 1925Stanezyk Sept. 8, 1928 Lasher July 10, 1934 Baum June 1, 1948 LivingstonJuly 12, 1949 FOREIGN PATENTS Country Date Great Britain Apr. 21, 1937Great Britain Oct. 30, 1945

